Oriental fruit flies can infest a wide array of crops, including tomatoes, peaches, mangoes, peppers and avocados, or about 95 percent of the crops grown in South Florida.
Jesse HaberFor the Miami Herald

Florida’s agriculture commissioner declared a state of emergency Tuesday to deal with an outbreak of an aggressive Asian fruit fly in part of Miami-Dade County’s fertile farmlands.

The declaration allows Agriculture Commissioner Adam Putnam to expand state authority and tap into additional resources, including law enforcement, to control the largest outbreak on record and maintain an 85-square-mile quarantine in the Redland, home to tropical fruit groves and some of the region’s largest packing houses.

As of Tuesday, the state had destroyed more than eight tons of infested fruit and trapped 158 flies.

“Miami-Dade County’s agriculture industry is a $1.6 billion industry, and we will use every weapon in our arsenal that’s necessary to eradicate this pest and protect Florida agriculture and our economy,” Putnam said in a statement Tuesday.

Traps first detected flies in the area on Aug. 28, about two weeks after a single fly turned up in an almond tree in Kendall. Another fly turned up last week southeast of Miami International Airport, but the outbreak appears to be contained to the Redland.

The state is working with the U.S. Department of Agriculture’s smuggling interdiction team to find the source of the flies, said Florida agriculture spokesman Mark Fagan. Because so many flies appeared so quickly, officials suspect an infested shipment of fruit was dumped.

Oriental fruit flies have been turning up in Florida for more than a decade, but never in such large numbers. As part of the state’s pest management program, about 56,000 traps are monitored statewide. But since 1999, the flies have been trapped in fewer than 10 locations and usually only one at a time.

The appearance of the Oriental fruit fly raises serious concern because it infests such a wide array of fruits and vegetables, including tomatoes, bananas, peppers, mangoes and avocado, or about 95 percent of the crops grown in South Florida. In Hawaii, where it was accidentally introduced in the 1940s, the fly now infects almost every commercial fruit crop, except pineapple and sugarcane. California, the only other state infested by the flies, has battled outbreaks every year since 1966, according to the California Department of Food and Agriculture.

Female flies inject their eggs into fruit, which the larvae in turn feed on, making any infected produce unsuitable for sale.

To deal with the outbreak, state workers have set an additional 674 traps, Fagan said. Male traps are more effective so efforts typically focus on catching males. But Fagan said female traps have also been set.

Workers are also using an organic insecticide to drench soil up to about 1,300 feet around fruit infested with fly larvae. So far, the larvae have only been found in mangoes on a single property, he said. The quarantine, which can only be lifted after 90 fly-free days, bans the removal of fruits or plants without a treatment plan approved by the state. About 460 plans have been approved, Fagan said.

In addition to expanding the state’s authority to treat the flies, spokeswoman Jennifer Meale said it also emphasizes the seriousness of the outbreak. The region produces much of the nation’s winter crops, including tomatoes, and represents about $1.6 billion of the state’s $123 billion agricultural industry.

While much of the mango season has ended for the region, avocados are still being harvested, Fagan said.

“But if there are mangoes on the ground, that would certainly be attractive to an Oriental fruit fly,” he said.

The largest outbreak of Oriental fruit flies in state history led Agriculture Commissioner Adam Putnam to declare a state of emergency Tuesday.
University of Florida Institute of Food and Agriculture Services